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Erdős problem #375

Is it true that for any $n,k\geq 1$, if $n+1,\ldots,n+k$ are all composite then there are distinct primes $p_1,\ldots,p_k$ such that $p_i\mid n+i$ for $1\leq i\leq k$?

Why this problem

Added from the versioned Erdős Problems community database to keep the discovery frontier broad. The first pass must validate the exact statement, status, literature, and a concrete verification contract.

Verification contract

Official database status is falsifiable; refine the exact certificate contract before any candidate claim.

Tracking
Difficulty
7/10
Attempts
1
Last attempt
2026-07-21 14:47 UTC
Source status
falsifiable
External validation
none
Techniques and harnesses
number theory
Resumable campaign memory

Research map

1 epochs · 0 promising · 0 blocked · 3 ruled out
Next session checkpoint

Resolve the closest-prior computational artifact trail before allocating further computation.

First action: Inspect https://mathoverflow.net/questions/248146/on-comparing-two-almost-injective-divisor-maps and its EACA-slide link, including archived targets, and record every source-code, data, range, and exception artifact.

Stop or redirect when: Stop when a runnable artifact permits independent replay of the smallest claimed failure and repair, or when the public trail ends without code or certificates and park the bound-extension lane.

Open leads
  • Recover and audit the Brox-Paseman provisional computation artifacts.
    Follow the EACA slides and MathOverflow links; inventory code, logs, exact failures, cover semantics, and replay the smallest failure if runnable artifacts exist.
  • Formalize the Hall-certificate contract or a finite interval checker in Lean.
    After disk repair, bootstrap Formal Conjectures and compile a minimal Hall-equivalence lemma with no sorry.
Strategy registry
  • isolated adversarial reconstruction
    Start from only a recovered provisional artifact and its stated range, reconstruct the smallest claimed exceptional interval using an independently written factor-divisor representation, and record the first discrepancy.
  • counterexample and witness search
    Factor each composite interval, construct its position-to-prime-divisor bipartite graph, test for a perfect matching, and emit a Hall-deficient subset on failure; compare against trial division plus exhaustive Hall-subset enumeration on a smaller domain.
    Reopen only if: Resume larger counterexample scanning only with a validated novelty target, requested range, structural observable, or actual Hall candidate; resume Lean only after several GB of verified free space.
Ruled out, with scope
  • Compile or extend the Lean formalization in the current host state.
    Cache unpacking failed with only 64 KB free disk; cleanup restored only 369 MB.
    Reopen only if: Verify several GB of free disk, rerun the prescribed bootstrap, and compile without sorry.
  • Use only the number of distinct prime factors in the whole interval product.
    This checks Hall's inequality only for the full left set; a proper subset can still be deficient.
    Reopen only if: A proof that the special consecutive-integer divisor graphs make the whole-set condition sufficient for every subset.
  • Treat a larger arbitrary local cutoff as a contribution.
    The accepted 2006 range and later provisional claims are vastly larger.
    Reopen only if: A counterexample, expert-requested range, validated best-bound improvement, or new structural theorem.
Complete history

Attempts on this problem

2026-07-21 14:47 UTCOpen-problem program · 17 min

Erdős problem #375

Baseline source and literature audit followed by validation of an exact Hall-certificate counterexample harness on a predeclared finite domain

What this run accomplished

The exact statement and current open status were audited. Historical methods, accepted and provisional computations, Lean semantics, software, verification contract, and external acceptance path were mapped. A mislabeled positive control inherited from the Terra delegate was corrected because its graph was actually deficient. The recorded experiment passed all seven controls, independently agreed through 1000, and found no failure among 779987 windows from 90407 composite starts with n+k<=100000. This is not a new bound or evidence for the universal conjecture.

Next: Audit the Brox-Paseman EACA slides, linked sources, and archives for public code, exact S-algorithm exceptions, range semantics, and validation artifacts.